Method of using catheters having a rapid exchange and over-the-wire operating mode

ABSTRACT

An intravascular catheter capable of both rapid-exchange and over-the-wire modes of operation having a relatively long proximal shaft portion, a relatively short distal section and an intermediate shaft section, which connects the proximal shaft section and the distal shaft section. In one embodiment, the intermediate shaft section includes a guide wire port and a first guide wire lumen which extends throughout both the intermediate and distal shaft section, and a second guide wire lumen which extends throughout the entire catheter shaft. In another embodiment, the intermediate shaft section includes a y-lumen junction which allows a first guide wire lumen introduced at the intermediate shaft section and a second guide wire lumen extending from the proximal end of the catheter shaft throughout the proximal shaft section to merge and communicate with a single distal guide wire lumen which extends from the intermediate shaft section to the distal end of the catheter shaft. In another embodiment, the catheter shaft includes a single guide wire lumen extending from the proximal end to the distal end wherein the guide wire lumen is defined by a proximal section and a distal section. The proximal section guide wire lumen includes a slit which allows a guide wire to be removed for rapid-exchange mode of operation or retained for over-the-wire mode of operation.

BACKGROUND OF THE INVENTION

[0001] The present invention generally relates to intravascularprocedures, such as treating carotid arteries and percutaneoustransluminal coronary angioplasty (PTCA), and particularly to anintravascular catheter which can be utilized in a rapid-exchange (RX) orover-the-wire (OTW) operating mode.

[0002] In typical PTCA procedures utilizing over-the-wire mode, adilation catheter is advanced over a guide wire slidably disposed withinan inner lumen of the dilation catheter into a patient's coronary arteryuntil the balloon on the distal extremity of the dilation catheter isproperly positioned across the lesion to be dilated. Once properlypositioned across the lesion, the flexible, relatively inelasticdilatation balloon on the catheter is inflated to a predetermined sizewith radiopaque liquid at relatively high pressures (e.g., generally4-20 atmospheres) to dilate the stenosed region of the diseased artery.One or more inflations of the balloon may be required to complete thedilation of the stenosis. After the last dilation, the balloon isdeflated so that the dilatation catheter can be removed from the dilatedstenosis and so that blood flow can resume through the dilated artery.

[0003] One significant improvement in dilatation catheters has been theintroduction of rapid-exchange type dilatation catheters. Thesecatheters have a short guide wire receiving sleeve or inner lumenextending through the distal portion of the catheter which extend from adistal guide wire port in the distal end of the catheter to a proximalguide wire port spaced proximal to the proximal end of the dilatationballoon. The proximal guide wire port is usually located at least about10 cm. and usually not more than about 50 cm. from the distal guide wireport. A slit is preferably provided in the catheter wall which extendsfrom the second guide wire port, preferably to a location proximal tothe proximal end of the inflatable balloon to aid in the removal of thecatheter from a guide wire upon withdrawal of the catheter from thepatient. The structure of the catheter allows for the rapid exchange ofthe catheter without the need for the use of an exchange wire or addinga guide wire extension to the proximal end of the guide wire. The designof this catheter has been widely praised by the medical profession andhas met with much commercial success in the market place because of itsunique design. The RX type dilation catheters of the assignee for thepresent invention, Advanced Cardiovascular Systems, Inc., have had asignificant impact in the market for rapid-exchange type dilationcatheters. Such products include dilatation catheters sold under thetradenames—The Alpha, The Streak, and The Ellipse.

[0004] However, there is one significant inconvenience with the use ofRX type dilatation catheter systems, namely, the inability to remove aguide wire already in place within a patient's vasculature during anangioplasty procedure without losing access to the vascular location.There has been no convenient way in which to withdraw an in-place guidewire and then advance a replacement guide wire without losing access tothe location of the distal end of the RX type dilatation catheter theshort guide wire receiving inner lumen in the distal extremity of a RXtype dilatation catheter. These instances occur when there is a need toreplace an in-place guide wire with another guide wire having adifferent structure, e.g., an intermediate or standard wire with a corewire which extends to the distal tip of the guide wire. The need towithdraw an in-place guide wire also occurs when the distal tip of thein-place guide wire needs to be reshaped.

[0005] U.S. Pat. No. 5,807,355 (Ramzipoor et al.), which has beenassigned to the present assignee, Advanced Cardiovascular Systems, Inc.,describes an intravascular catheter with both RX and OTW operativemodes. The Ramzipoor et al. patent is incorporated herein by reference.While this catheter provides for RX and OTW modes of operation, which isby choice of the operating physician, only one mode may be used at atime thus limiting the effective usefulness of the device. Additionally,the Ramzipoor dual mode catheter does not provide for a smooth RX guidewire exit port for used during RX modes. During such use, the RX guidewire will deform during passage through the expanded helical coil guidewire port. The need still exists therefore for a catheter which allowsfor simultaneous dual mode operation and which provides for a smoothexit notch. The present invention satisfies these and other needs.

SUMMARY OF THE INVENTION

[0006] This invention is directed to an elongated intravascular catheterwhich can be utilized in a rapid-exchange (RX) and/or an over-the-wire(OTW) mode of operation to perform an intravascular procedure, andparticularly to a balloon dilatation catheter which can be used withinthe coronary arteries of a human patient during an angioplastyprocedure.

[0007] The intravascular catheter of the invention generally comprisesan elongated shaft with proximal and distal ends, a port in the distalend, a first lumen extending through the catheter from the port in thecatheter distal end to a location spaced proximal to the proximal end ofthe balloon, and a second lumen extending through the catheter from theproximal end to the port in the distal end of the catheter. The cathetershaft has an elongated proximal section, an intermediate section, arelatively short distal section and a balloon or other means to performan intravascular procedure on the distal section.

[0008] In the RX mode, the intravascular catheter can be advanced overan in-place guide wire within the first guide wire lumen while holdingonto the proximal extremity of the guide wire extending out of thepatient, until the distal end of the catheter is disposed within adesired location of the patient's vascular system. The in-place guidewire is external of the catheter proximal to the opening in theintermediate shaft section of the catheter. In this manner, the in-placeguide wire can be removed by pulling on the proximal extremity thereofwhich extends out the patient and a replacement guide wire can beintroduced into the proximal end of the catheter shaft, advanced throughthe catheter shaft in the second guide wire lumen in the OTW mode andthen out the port in the distal end of the catheter.

[0009] For coronary artery use, the opening in the intermediate shaftsection is preferably spaced longitudinally at least 30 cm from thedistal end of the catheter shaft to ensure that it remains within aguiding catheter when the distal shaft section extends out into thepatient's coronary artery.

[0010] In one embodiment, the distal shaft section of the catheterincludes dual guide wire lumens, a first guide wire lumen entering theRX guide wire port in the intermediate shaft section, extendingthroughout the intermediate shaft section, the distal shaft section andthen out the opening in the distal end of the catheter, and a secondguide wire lumen extending throughout the entire catheter from theproximal shaft section to the distal shaft section and then out the portin the distal end of the catheter. The first guide wire lumen slidablyreceives an RX guide wire and the second guide wire lumen slidablyreceives an OTW guide wire.

[0011] In another embodiment of the invention, a y-section inner memberhaving a slidable insert jacket provides a first (RX) guide wire lumenand a second (OTW) guide wire lumen of the proximal shaft section tocommunicate, forming a notch junction in the intermediate shaft section,wherein a single lumen, the distal section guide wire lumen, is formedwhich extends throughout the distal shaft section of the catheter andthen out the port in the distal end of the catheter. The slidable insertjacket allows the physician to dictate the mode of operation. For the RXmode, the slidable insert jacket is pushed forward blocking off thesecond guide wire lumen at the notch junction and allowing the firstguide wire lumen to be in fluid communication with the distal sectionguide wire lumen of the distal shaft section. For the OTW mode, theslidable insert jacket is slightly pulled back thus allowing the secondguide wire lumen to be in fluid communication with the distal sectionguide wire lumen of the distal shaft section. Therefore, by a simplepull or push of the slidable insert jacket, the physician may chooseeither RX or OTW modes of operation.

[0012] In yet another embodiment, the proximal shaft section of thecatheter comprises a lumen having a “peel-away” slit. The peel-awayproximal shaft section serves both OTW and RX modes of operation. Theguide wire lumen of the proximal shaft section has a slit which allowsfor the guide wire to be “peeled-away” and removed from the guide wirelumen, wherein the slit width is slightly smaller than the guide wirediameter thereby allowing the guide wire to remain within the lumenduring the OTW mode of operation. The guide wire lumen slit, because ofthe deformable character of the material used, allows for the guide wireto be “peeled-away” or pulled out of the guide wire lumen via the guidewire lumen slit, thus allowing the RX mode of operation. The guide wirelumen slit runs throughout the proximal shaft section and ends in alocation proximal to the distal shaft section at the intermediate shaftsection. The intermediate shaft section is reinforced with a peel-awaystrain relief which ensures that the guide wire lumen slit will notpropagate distally into the distal shaft section of the catheter.

[0013] Other features and advantages of the present invention willbecome apparent from the following detailed description, taken inconjunction with the accompanying drawings, which illustrate, by way ofexample, the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014]FIG. 1 is an elevational view, partially in section, of oneembodiment of the invention.

[0015]FIG. 2 is a transverse cross-sectional view of the embodimentshown in FIG. 1 taken along lines 2-2.

[0016]FIG. 3 is a transverse cross-sectional view of the embodimentshown in FIG. 1 taken along lines 3-3.

[0017]FIG. 4 is an elevational view, partially in section, of anotherembodiment of the invention.

[0018]FIG. 5 is a transverse cross-sectional view of the embodimentshown in FIG. 4 taken along lines 5-5.

[0019]FIG. 6 is a transverse cross-sectional view of the embodimentshown in FIG. 4 taken along lines 6-6.

[0020]FIG. 7 is a transverse cross-sectional view of the embodimentshown in FIG. 4 taken along lines 7-7.

[0021]FIG. 8 is an elevational view, partially in section, of theembodiment shown in FIG. 4, configured for use in over-the-wire mode inwhich the insert sleeve is slightly pulled back.

[0022]FIG. 9 is an elevational view, partially in section, of anotherembodiment of the invention.

[0023]FIG. 10 is a transverse cross-sectional view of the embodimentshown in FIG. 9 taken along lines 10-10 depicting the peel-away slit ofthe proximal shaft section.

[0024]FIG. 11 is a transverse cross-sectional view of the embodimentshown in FIG. 9 taken along lines 11-11.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] The present invention provides for treatment of diseased vesselsand arteries by giving the physician the option to utilize either an OTWor RX mode operation using the same catheter. In keeping with theinvention, reference is made to FIGS. 1-3 which depict one embodiment ofthe current dual guide wire lumen catheter invention. In particular, thecatheter 10 includes an elongated catheter shaft 12 with a relativelylong proximal shaft section 14, an intermediate shaft section 16, and arelatively short distal shaft section 18. The catheter shaft 12 has afirst guide wire lumen 20 which begins at the RX guide wire port 26located near the distal end of the intermediate shaft section 16 andextends throughout the distal shaft section 18 and then out the distalend guide wire port 34 in the distal end of the catheter 10. Thecatheter also includes a second guide wire lumen 22 which extendsthroughout the catheter shaft 12 from the proximal end (not shown) ofthe proximal shaft section 14 to the distal end of the distal shaftsection 18 and then out the distal end guide wire port 34. An inflationlumen 24 extends throughout the catheter shaft 12 from the proximal endof the proximal shaft section 14 to balloon opening 32 located at oneend of the distal shaft section 18. A guide wire port 34 is provided inthe distal end of the distal shaft section 18 which is in fluidcommunication with the first guide wire lumen 20 and the second guidewire lumen 22. Both the first guide wire lumen 20 and the second guidewire lumen 22 are capable of slidably receiving a guide wire. The distalshaft section 18 is further provided with a dilatation balloon 28 whichhas an interior 30 in fluid communication with the inflation lumen 24through balloon opening 32.

[0026] As seen in FIG. 1, the proximal shaft section 14 and the distalshaft section 18 are interconnected at the intermediate shaft section16. The proximal shaft section 14 is coupled to the distal shaft sectionby any means of adhesion, including laser bonding or fusion, glueing ormelting. The communication between the proximal shaft section 14 and thedistal shaft section 18 is provided by RX guide wire port 26.Additionally, the distal shaft section is in fluid communication with adilatation balloon 28, the proximal end of the balloon is incommunication with the distal shaft section via the balloon opening 32and the distal end 31 of the balloon is attached to the distal end ofthe distal shaft section 18.

[0027]FIG. 2 depicts a cross-sectional view of the intermediate shaftsection 16 of FIG. 1 taken along lines 2-2 wherein the intermediateshaft section encompasses the first guide wire lumen 20 and the proximalshaft section 14, which encompasses the second guide wire lumen 22 andthe inflation lumen 24. FIG. 3 illustrates a cross-sectional view of thedistal shaft section 18 which encompasses the first guide wire lumen 20,the second guide wire lumen 22 and the inflation lumen 24.

[0028]FIGS. 4 through 8 depict a preferred embodiment of the currentinvention. In particular, FIG. 4 depicts a notch junction catheterhaving an elongated catheter shaft 52 with a relatively long proximalshaft section 54, an intermediate shaft section 56, and a relativelyshort distal section 58. The catheter shaft 52 has a first guide wirelumen 60 which begins at the RX guide wire port 66, located near theproximal end of the intermediate shaft section 56, and which extendsthroughout the intermediate shaft section 56. The first guide wire lumencommunicates with the distal section lumen 68 at the lumen y-junction72. A second guide wire lumen 62, which begins at the proximal end ofthe proximal shaft section 54, extends throughout the proximal shaftsection 54 and the intermediate shaft section 56 and communicates withthe distal section lumen 68 at the lumen y-junction 72. A distal sectionlumen is in fluid communication with the first guide wire lumen 60 andthe second guide wire lumen 62 at the lumen y-junction 72. The distalsection lumen 68 extends from the lumen y-junction 72 throughout thedistal shaft section 58 to the distal end of the catheter shaft 52.

[0029] As seen in FIG. 4, insert jacket 70 is used to determine the modeof operation, either the RX or OTW models. During use, insert jacket 70is inserted into the RX guide wire port. For the RX mode of operation,the insert jacket is pushed distally into the first guide wire lumenuntil there is closed communication with the distal section guide wirelumen 68, thus allowing a guide wire to be slidably received by thedistal section guide wire lumen 68 through the insert jacket 70 placedwithin the first guide wire lumen 60. As depicted in FIG. 8, for the OTWmode of operation, the insert jacket is pulled proximally or placedslightly proximal to the distal section guide wire lumen 68 within thefirst guide wire lumen 60, thereby allowing the second guide wire lumen62 to be in fluid communication with the distal section guide wire lumen68. This fluid communication between the second guide wire lumen 62 andthe distal section guide wire lumen 68 allows for a guide wire to extendthroughout the catheter shaft 52 in the OTW mode of operation.

[0030] For further clarification, FIGS. 5-7 depict cross-sectional viewstaken at various locations along the catheter shaft 52. FIG. 5 depicts across-sectional view of the proximal shaft section 54 of FIG. 4 takenalong lines 5-5 wherein the proximal shaft section 54 encompasses thesecond guide wire lumen 62 and the inflation lumen 64. The insert jacket70 is located externally of the proximal guide wire lumen. FIG. 6depicts a cross-sectional view of the intermediate shaft section 56 ofFIG. 4 taken along lines 6-6 wherein the intermediate shaft section 56encompasses the first guide wire lumen 60 which further encompasses theinsert jacket 70 and the proximal shaft section 54, which encompassesthe second guide wire lumen 62 and the inflation lumen 64. FIG. 7depicts a cross-sectional view of the distal shaft section 58 of FIG. 4taken along lines 7-7 wherein the distal shaft section 58 encompassesthe distal section guide lumen 68 and the inflation lumen 64.

[0031] FIGS. 9-11 illustrate yet another embodiment of the invention. Inparticular, FIG. 9 depicts the peel-away catheter having an elongatedcatheter shaft 82 with a relatively long proximal shaft section 84, anintermediate shaft section 86, and a relatively short distal section 88.The catheter shaft 82 has a guide wire lumen comprised of the proximalsection guide wire lumen 90 and distal section guide wire lumen 92, aninflation lumen 98, a balloon 100 located in the distal shaft section88, and an optional support mandrel 110 providing support for thecatheter shaft 82. The proximal shaft section comprises an inflationlumen 98, a proximal section guide wire lumen 90 and a guide wire lumenslit 94. The guide wire lumen slit 94 is aligned parallel to and alongthe length of the proximal shaft section 84 and provides the peel-awaymechanism of the proximal shaft section 84. The guide wire lumen slit 94is smaller in width than the diameter of the typical guide wire,therefore during use, the guide wire is retained within the proximalsection guide wire lumen unless force is exerted by the physician topull the guide wire out of the guide wire lumen slit 94 and peel it awayfrom the catheter.

[0032] The intermediate shaft section 86 includes the proximal sectionguide wire lumen 90 wherein the proximal section guide wire lumen 90comes into fluid contact with the distal section guide wire lumen 92,the inflation lumen 98, and the peel-away strain relief 96. Thepeel-away strain relief 96 is positioned on the outside circumference ofthe intermediate shaft section 86 and provides resistance from thepropagation of the guide wire lumen slit 94 of the proximal shaftsection 84 into the distal shaft section 88. The peel-away strain reliefmay be constructed of the same material as the catheter shaft.

[0033] The distal shaft section 88 includes the inflation lumen 98, theballoon 100 and the distal section guide wire lumen 92. The distalsection guide wire lumen 92 is in continuous contact and in fluidcommunication with the proximal section guide wire lumen 90 at theintermediate shaft section 86 as described above. The balloon is locatedat the distal end of the distal shaft section and is defined by aproximal end, distal end, and an interior. The proximal end of theballoon 100 is in fluid communication with the inflation lumen 98 viathe balloon opening 104, the distal end of the balloon defines the endof the catheter shaft and ends at the distal end guide wire port 112.The proximal end of the balloon 100 is permanently connected to thedistal shaft section 88 at a location slightly proximal to the end ofthe catheter shaft 82.

[0034] For further clarification, FIGS. 10 and 11 depict cross-sectionalviews taken at various locations along the catheter shaft 82. FIG. 10depicts a cross-sectional view of the proximal shaft section 84 of FIG.9 taken along lines 10-10 wherein the proximal shaft section 54encompasses the proximal section guide wire lumen 90 and the inflationlumen 98. The guide wire lumen slit 94 allows for an opening in theproximal section guide wire lumen 90, however, because the guide wirelumen slit 94 typically is closed or at least defines a very narrow gapthat is smaller than the diameter of the typical guide wire to be usedwith this catheter, the guide wire is retained within the proximalsection guide wire lumen 90 unless force is exerted by the operatingphysician to pull the guide wire out of the guide wire lumen slit 94.FIG. 11 depicts a cross-sectional view of the distal shaft section 88 ofFIG. 9 taken along lines 11-11 wherein the distal shaft section 88encompasses the distal section guide wire lumen 92 and the inflationlumen 98. Both FIGS. 10 and 11 illustrate the optional support mandrelwhich adds stiffness to the catheter shaft which allows for easierhandling of the catheter during introduction into the patient'svasculature.

[0035] From FIG. 9 it is seen that for the RX mode of operation, theguide wire is inserted in the proximal end of the proximal shaft section84 and into the proximal section guide wire lumen 90. The guide wiretraverses the length of the proximal section guide wire lumen 90 intothe distal section guide wire lumen 92 and out the distal end guide wireport 112. After the catheter is in place in the patient's vasculature,the guide wire lumen slit 94 in the proximal shaft section guide wirelumen 90 allows for the guide wire to be quickly removed by pulling itout of the guide wire lumen slit. Furthermore, as seen from FIG. 9, forthe OTW mode of operation, the guide wire is inserted in the proximalend of the proximal shaft section 84 into the proximal section guidewire lumen 90. The guide wire traverses the length of the proximalsection guide wire lumen 90 into the distal section guide wire lumen 92and out the distal end guide wire port 112. After the catheter is inplace in the patient's vasculature, the guide wire remains in theproximal section guide wire lumen 90 and may be removed by pulling itout of the catheter shaft by the operating physician, at the proximalend of the proximal shaft section 84.

[0036] The use of the catheters of the invention for the most partfollow the procedures described in U.S. Pat. No. 5,135,535 (Kramer),assigned to the present assignee (Advanced Cardiovascular Systems,Inc.). The Kramer patent is incorporated herein by reference.

[0037] The catheter shaft of the invention can be formed by conventionaltechniques well known in the art, e.g., extruding from a variety ofpolymer materials already found useful in intravascular catheters suchas polyethylene, polyimide, polyamide, PVC, polyester (e.g., Hytrel) andhigh strength polymers such as polyetheretherketone (PEEK). The variouscomponents of the catheter can be joined by conventional adhesives, suchas acrylonitrile based adhesives, heat shrinking, fusion bonding and thelike.

[0038] The traverse dimensions of the catheter shaft and the guide wirelumens are for the most part determined by the transverse dimensions ofthe guide wire to be used in the catheter. Typically, the guide wire isabout 0.008 to about 0.035 inch (0.2-0.9 mm) in diameter. The guide wirelumen is configured to slidably receive the guide wire, i.e., it shouldbe about 0.001 to about 0.005 inch (0.025-0.13 mm) larger than the guidewire diameter. The catheter shaft is sufficiently long to extend fromoutside the proximal end of the guiding catheter, which likewise extendsout of the patient during the procedure, to a vascular location wherethe procedure is to be performed. Typically, the catheter is about 135cm in length. In the peel-away catheter embodiment, the guide wire lumenslit 94 should have a width smaller than that of the guide wire diameterin order to retain the guide wire within the proximal section guide wirelumen 90 for the OTW mode of operation. Additionally the slit widthshould be sufficiently wide enough to allow deformation when force isapplied by the operating physician in order to pull the guide wire outof the proximal section guide wire lumen via the guide wire lumen slitfor the RX mode of operation.

[0039] While the invention is described herein in terms of a dilatationcatheter, those skilled in the art will recognize that it is applicableto a variety of intravascular catheters. Additionally, while severalparticular forms of the invention have been illustrated and described,it will be apparent that to those skilled in the art that variousmodifications can be make without departing from the spirit and scope ofthe invention. Although individual features of embodiments of theinvention may be shown in some of the drawings and not in others, thoseskilled in the art will recognize that individual features of oneembodiment of the invention can be combined with any or all the featuresof another embodiment.

What is claimed:
 1. An intravascular catheter comprising: an elongatedshaft defined by a proximal section, an intermediate section and adistal section wherein said proximal shaft section is attached to saiddistal section at said intermediate section; a first guide wire port insaid intermediate section; a first guide wire lumen extending thereinfrom said first guide wire port throughout said intermediate shaftsection and said distal shaft section; a second guide wire port at theproximal end of said proximal section; a second guide wire lumenextending from said second guide wire port throughout said proximal,intermediate and distal shaft sections; a balloon attached to saiddistal shaft section to perform an intravascular procedure; and aninflation lumen extending from said proximal end of said proximal shaftsection to the proximal end of said balloon at a balloon opening and influid communication with said balloon at said balloon opening.
 2. Theintravascular catheter of claim 1 wherein said first guide wire port andsaid second guide wire port are capable of slidably receiving a guidewire.
 3. An intravascular catheter comprising: an elongated shaftdefined by a proximal section, an intermediate section and a distalsection wherein said proximal shaft section is attached to said distalsection at said intermediate section; a first guide wire port in saidintermediate section; a first guide wire lumen extending therein fromsaid first guide wire port; a second guide wire port at the proximal endof said proximal section; a second guide wire lumen extending from saidsecond guide wire port throughout said proximal and intermediate shaftsections; a distal section guide wire lumen extending from saidintermediate shaft section to the distal end of said distal shaftsection; a lumen y-junction in said intermediate shaft section whereinsaid first guide wire lumen and said second guide wire lumen communicatein a y-junction to said distal section guide wire lumen; a balloonattached to said distal shaft section to perform an intravascularprocedure; and an inflation lumen extending from said proximal end ofsaid proximal shaft section to the proximal end of said balloon at aballoon opening and in fluid communication with said balloon at saidballoon opening.
 4. The intravascular catheter of claim 3, furthercomprising an insert jacket positioned within the first guide wire lumenvia the first guide wire port whereby the operating physician can chooseeither a rapid-exchange or an over-the-wire mode of operation.
 5. Anintravascular catheter comprising: an elongated shaft defined by aproximal section, an intermediate section and a distal section whereinsaid proximal shaft section is attached to said distal section at saidintermediate section; a first guide wire port at the proximal end ofsaid proximal section; a guide wire lumen extending throughout saidproximal, intermediate and distal shaft sections defined by a proximalsection located in said proximal shaft section and a distal sectionlocated in said distal shaft section; a guide wire lumen slit extendingthe length of said proximal shaft section and which provides for a guidewire to be peeled-away from the proximal section guide wire lumen; astrain relief located around the circumference of said intermediateshaft section for providing resistence from the propagation of saidguide wire lumen slit of said proximal section guide wire lumen intosaid distal section guide wire lumen of said distal shaft section; anexpandable member attached to said distal shaft section to perform anintravascular procedure; and an inflation lumen extending from saidproximal end of said proximal shaft section to the proximal end of saidexpandable member at an opening in said expandable member and in fluidcommunication with said balloon at said opening.
 6. The intravascularcatheter of claim 5, wherein said guide wire lumen slit has a widthsmaller than the diameter of a guide wire to be used, thereby allowingthe guide wire to be retained within said proximal section guide wirelumen during the over-the-wire mode of operation unless force is exertedto pull the guide wire out of said proximal section guide wire lumenthrough said guide wire lumen slit for the rapid-exchange mode ofoperation.
 7. The intravascular catheter of claim 6, further comprisinga removable support mandrel embodied in said catheter shaft forproviding stiffness to said catheter shaft for easier handling of thecatheter during introduction into the vasculature.